The garment industry has for many years relied upon manual operation in the fabrication ("cutting and sewing") of garments with negligible advancements being made in automation and machinery to reduce cost, improve quality and uniformity, and to increase production. Numerous manual operations necessary for end finishing waistbands in garments such as pants, skirts, and shorts provide troublesome, time consuming, and tedious operations. Presently, waistbands are formed by folding and seaming an elongated section of fabric lengthwise, which section is then secured to the upper edge of a garment with the ends of terminal portions of the waistband that are unfinished extending beyond the side edges of the garment. The free terminal end portions must then be turned inwardly through an inversion of the end portion to tuck the end portion inwardly into the area between the plies of the secured portion of the waistband in order to form a coincident finished edge preparatory for seaming on a sewing machine. In the past, until the invention of the apparatus described in U.S. Pat. No. 3,507,234 to Bryan, such operations were accomplished manually with the result that production bottlenecks problems occurred particularly in the manufacture of medium and low priced trousers, work pants, jeans, sport clothes, and among other apparel in which a waistband or comparable end finishing is required.
With the advent of the apparatus described and illustrated in U.S. Pat. No. 3,507,234, the tedious manual operations were substantially eliminated with an apparatus that could mechanically invert the free terminal end portion of the waistband and automatically transport it to a sewing station for closing the finished edge. Such apparatus was substantially completely mechanical in that the timing and activation of the instrumentalities that perform the clamping, spreading, inverting, releasing, and transportation of the end portion to the sewing head were effected by a main rotating cam shaft which in turn operated a series of cams, levers, springs, slides, tie rods, and the like to perform the inverting and transporting operations. While this approach represented a remarkable improvement over the previous manual operations, as time went along, new problems and the need for further improvements arose.
For example, since the driving force and relative timing of all the operations were generated from the single rotating cam shaft, where it became necessary to adjust critical timing intervals for one reason or another, such operation was very difficult to accomplish. The system of cams, levers, springs, slides, tie rods and the like was extremely complicated and as parts began to wear, this had a considerable effect on the relative operation and timing of the entire apparatus. Further, in the referenced patent, the transporting of the end portion from the inverting head to the sewing apparatus required a multi-planar movement and rotation of the end portion. As a result, it was complicated and difficult to position the finished edge in proper alignment with the sewing head to effect a seam that was consistently acceptable and parallel to the finished edge. Also, the inverting of the tubular end portion of the waistband back into itself resulted in a finished edge comprising an extremely bulky area of fabric adjacent the upper edge of the garment (four plies in the waistband, two folds, and at least one ply in the garment upper section). Such a gathering of a fabric, such as denim used in the manufacture of jeans and skirts, becomes extremely bulky and when presented to the sewing head, would sometimes result in a seam in which the stitches were unsatisfactorily formed or was otherwise unsatisfactory. Therefore, even though the apparatus described and illustrated in U.S. Pat. No. 3,507,234 represented a remarkable improvement over the manual technique for inverting and seaming the terminal end portions of the waistband, there resulted a substantial number of unacceptable garments and further improvements were sought.
In the machine according to the present invention, the spreading of the fabric plies, the folding of the terminal end portions, the transporting of the waistband to the sewing head, and the positioning of the waistband in position for the sewing operation are accomplished by hydraulic and pneumatic cylinders operated responsive to an electro-mechanical control system. The use of hydraulic and pneumatic cylinders and electro-mechanical controls significantly simplify the apparatus, make the timing easier to adjust, and minimize the wear on the operative parts of the apparatus. During the folding operation, after the terminal end portions have been inverted, while the fabric plies are still spread apart, and before the impaling tongue has been reintroduced into the waistband, a flattening operation is performed on the area of the fabric immediately adjacent the finished edge to reduce the bulk thereof in preparation for the sewing operation. Toward this end, a pair of opposed, vertically aligned "flattening" feet are brought together with the fabric portion to be treated therebetween.
Once the folding or inverting and flattening operation has been completed, the waistband is transferred in a single planar movement to the sewing head assembly where the waistband is received and gripped by a gripping apparatus, then positively moved inwardly to a stop means properly aligned beneath the sewing head. This eliminates the multi-planar movement of the original apparatus and also positively positions the finished edge of the waistband portion against a stop member to ensure that the ensuing seam extends parallel to and closely adjacent the finished edge. The resulting product then is improved because the combination of the flattening operation and the positive positioning of the finished edge beneath the sewing head ensures that a consistently acceptable seam is formed parallel to and adjacent the finished edge on each and every garment. As a result, the number of unacceptable garments is considerably reduced.
It is therefore one object of the present invention to provide an improved waistband end finishing apparatus and method which facilitates the closing of the open end of a waistband.
Another object of the present invention is to provide an end finishing apparatus and method of the type described in which the fabric area adjacent the finished edge is flattened subsequent to the folding operation and preceding the sewing operation.
Yet another object of the present invention is to provide a waistband end finishing apparatus and method of the type described in which subsequent to the folding operation, the waistband is transferred in a simple, uniplanar path to the sewing head assembly where it is positively positioned against a stop means in preparation for the seaming operation.